To improve the soil by promoting internal drainage, or in order to assure the longevity of existing drains and avoiding their warping, there are in existence sheets of continuous textile fibers, imputrescible, woven or not woven which are used in covering the zones to be improved. Some of these sheets constitute good drainage and filtration elements as well as, in certain cases, a means for the distribution of loads. In cases when these sheets form, or are placed to form, a heterogenic ensemble, the friction coefficient between layers is not always sufficient to avoid full displacement of a layer of soil relative to the layers. Furthermore, such sheets require generally a horizontal placement, or to be placed on relatively slight slopes which do not possess any natural means of anchorage. Finally, whatever their situation, the sheets must always be covered with shaping materials, because by themselves they do not contribute to the stability of the structure. The goal sought is, in effect, the conservation of the structure not by mechanical consolidation, but by soil improvement and by the better distribution of loads from one part to another part. Properly speaking, these two results contribute together to safeguard the structure but without having it consolidated.